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Check out the statistics applet at:
<http://espse.ed.psu.edu/edpsych/faculty/rhale/Statistics/statlets/ free/calib.htm>
Using it (and treating the resistivity as the dependent variable in the calibration plot), using the data you provided, I get, for r=62 nano-ohm meters, with the confidence level for the prediction interval set to 68.3%:
p = (33.1 +/- 7.4) %
________________________________
From: phys-l-bounces@carnot.physics.buffalo.edu on behalf of Ludwik Kowalski
Sent: Sun 8/5/2007 5:54 PM
To: Forum for Physics Educators
Subject: Re: [Phys-l] calibration
Aug 5, 2007, at 2:23 PM, Folkerts, Timothy J wrote:
Finding the prediction interval for a linear regression is a little
more complicated than just finding the St Dev of the various points.
It may be convenient to define the uncertainty of p as the standard
deviation of such fluctuations, but it is not the standard practice.
You should perhaps check a stats book for more info on the topic.
A quick run of the data through Minitab suggests that the +/-1 stdev
prediction interval (68.3% confidence level) for r = 0.62 is p =
30.25 +/- 6.5. This is half again as large as the interval you list.
The size of the prediction interval also changes across the range of
the graph. . . .